This invention relates to thermal transfer printing apparatus in which ink is transferred from a thermal transfer ink ribbon to a print receiving medium by selective energisation of thermal printing elements of a thermal print head.
In thermal transfer printing apparatus, the thermal transfer ink ribbon is interposed between the thermal printing elements and the print receiving medium. The thermal transfer ink ribbon includes an ink layer carried on a ribbon substrate and the thermal transfer ink ribbon is orientated with the ink layer of the ribbon in contact with the print receiving medium. The print receiving medium is fed by feeding means past the thermal printing elements of the print head and, as a result of frictional engagement between the ink layer of the ribbon and the print receiving medium, the ink layer of the ribbon adheres to the print receiving medium and thereby the ribbon is drawn with the print receiving medium as the print receiving medium is fed past the print head. The thermal printing elements are disposed in a line extending transversely to the direction of feeding of the print receiving medium and are selectively energised by an electric current to cause heating of the printing elements to transfer ink from the ink layer to the print receiving medium. After passing the print elements, the used ribbon is peeled from the print receiving medium and is wound onto a take-up spool by driving the take-up spool. Usually the drive to the take-up spool is provided by means of a dedicated electric drive motor controlled to impart sufficient tension to peel the ribbon from the print receiving medium.